Modeling of Matrix Failure in Ceramic Matrix Composites

Abstract

This paper investigates failure criteria used in modeling matrix failure in unidirectional and cross-ply laminates of ceramic matrix composites. In particular, the critical matrix strain energy (CMSE) criterion, as recently introduced by the authors, is examined in detail. In principle, a failure criterion, such as CMSE, which does not require many empirical constants, is desired. This CMSE approach provides a simple closed-form estimate for the matrix crack density in ceramic matrix composites when subjected to monotonic tensile loading. The proposed criterion can be easily extended to more complex loading conditions (for example, fatigue) and laminate geometries. Other matrix failure criteria, available in the literature, are also discussed. The CMSE criterion does an adequate job of estimating the evolution of matrix damage in both unidirectional and cross-ply laminates.